Traditionally, products to be packaged, especially fragile and heavy products, are protected against impact by means of wedging systems before they are enclosed in wrapping or in crates. The wedging systems are generally made of blocks of polystyrene in the shape of wedges or half-shells of a certain rigidity to prevent direct transmission of impacts. When this type of package is shipped or handled, however, the packaged product is inevitably subjected to vibration and slight shifting and rubbing inside the wedging system, which has the effect of leaving markings and degrading the external appearance of the packaged product, by deterioration of the paint finish, for example. One means currently employed to eliminate this risk of degradation consists of surrounding the product with flexible plastic wrapping before adding the wedging system. The wrapper is then subject to rubbing and vibration, but because of its flexibility, it protects the product and prevents the it from suffering any marking or deterioration.
Nevertheless, use of a protective wrapper of this kind poses certain disadvantages. In particular, when a heavy product is being packaged, it is often suspended by a gripping element, for example an articulated sucker applied to the upper surface of the product, to facilitate handling during this operation. A first disadvantage becomes evident when the wrapper is slipped around the product and the gripping element interferes with the movement and closure of the wrapper. Then, when it is desired to remove the gripping element, the wrapper interferes with its movement. The packaging operation cannot be automated under these conditions, at least not during these latter two phases.
In addition, closure of such a wrapper is more difficult; once the product has been wrapped, it is then necessary to reclose the opening by means of adhesive tape, for example, which also entails lost time and consequently additional expense.